Articles de revues : « Active fixtures »

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MÖHRING, H. Christian, Werner GESSLER, Alexander KÖNIG, Le Trung NGUYEN et Q. Phuc NGUYEN. « Modular intelligent fixture system for flexible clamping of large parts ». Journal of Machine Engineering 4, n^o 17 (12 décembre 2017) : 29–39. http://dx.doi.org/10.5604/01.3001.0010.7003.

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In this work a modular intelligent fixture system for flexible clamping of large parts is presented. The fixture modules consist of a hybrid material structure involving metal frame elements and mineral casting. These modules can be combined and connected to realize fixtures adapted to the geometry of the workpiece and requirements of the machining processes. By integrated pipes and interfaces, an internal hydraulic supply and active cooling is possible even for combined modules. Temperature and acceleration sensors allow for an active thermal control and process monitoring. The modules and first test fixtures are investigated in experiments.

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Chitariu, Dragoş-Florin, et Adriana Munteanu. « Research on 3D printed fixture components ». MATEC Web of Conferences 178 (2018) : 02008. http://dx.doi.org/10.1051/matecconf/201817802008.

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Fixtures are used for orientation, positioning and tightening of the workpiece during machining, control and assembly. The main fixture requirements are: orientation, positioning and tightening precision in accordance with the machining requirements. The materials used for fixture components, especially, supports and clamping mechanism are, usually, alloy steel with HRC hardness up to 55-60 HRC. These components are machined to high level of precision thus assuring the overall precision of the fixture. In order to achieve high stiffness and a good dampening capacity the fixture become, usually, very heavy. In the case of manually operated fixtures light weight is an advantage; also there are operations such as inspection, assembly where the operating forces are low. In this case lightweight materials can be used for fixture construction. In this paper the FDM (Fused Deposition Modeling) 3D printing technology is used. Support buttons and v-block fixture components were selected and 3D printed. The effect of printing orientation of active surfaces of support was analysed. The dimensional accuracy and surface roughness on the active surface were measured. Experimental results indicate that surface roughness is dependent on the orientation of the printed workpiece.

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Bowyer, Stuart A., Brian L. Davies et Ferdinando Rodriguez y Baena. « Active Constraints/Virtual Fixtures : A Survey ». IEEE Transactions on Robotics 30, n^o 1 (février 2014) : 138–57. http://dx.doi.org/10.1109/tro.2013.2283410.

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Cruz-Ramírez, S. Rolando, Tatsuo Arai, Yasushi Mae, Tomohito Takubo et Kenichi Ohara. « Recognition and Removal of Interior Facilities by Vision-Based Robot System ». Journal of Robotics and Mechatronics 22, n^o 1 (20 février 2010) : 50–64. http://dx.doi.org/10.20965/jrm.2010.p0050.

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For future dismantling jobs in the renovation of the interiors of office buildings, we propose a robotic dismantling system that will assist human workers with the hard works. As an application of the robotic system, this paper presents the process of removing ceiling fixtures, such as Lamp Panels (LPs) and Air Conditioning Vents (ACVs), by man and robot. In this collaboration, a robot arm provides assistance by holding and collecting the fixtures, and the human worker only removes screws and/or nuts. In order to lead the robot to a holding position, the human worker indicates a position on the fixture to the robot with brief and simple instructions. The robot estimates the pose of the fixture through 3D model-based object recognition with a hand-mounted stereo camera. The integration of multiple viewpoints for the robot with an active lighting system enhances the recognition performance against both natural lighting changes at the site and the variability in the pose between the camera and the object to be recognized. As a verification experiment, the sequential removal of several different ceiling fixtures is presented. In this experiment, robust recognition is achieved with an average accuracy of 10 mm. The feasibility of the system is verified by using the completion time and the precision requirements in a practical environment.

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Townes, Maryanne. « Jigs and Fixtures : Design Review Guidelines for the Ergonomics Engineer ». Proceedings of the Human Factors and Ergonomics Society Annual Meeting 38, n^o 15 (octobre 1994) : 960. http://dx.doi.org/10.1177/154193129403801532.

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Traditionally, the ergonomics engineer has not played an active role in the design of jigs and fixtures used to manually assemble parts. This is problematic, since tool redesigns are often infeasible due to cost and production constraints. Therefore, less effective measures must be used to control ergonomic hazards, since the hazard(s) cannot be engineered out during the design process. References, guidelines and checklists used by many tool designers do not include ergonomic engineering principles and methods. In addition, many ergonomics engineers may not be schooled in the elements of jig and fixture design, which may reduce their effectiveness as part of the tool design team. The purpose of this paper is to provide the ergonomics engineer with an overview of the design process, and proffer guidelines to assist in the review of jig and fixture designs.

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Sallese, Lorenzo, Niccolò Grossi, Jason Tsahalis, Antonio Scippa et Gianni Campatelli. « Intelligent Fixtures for Active Chatter Control in Milling ». Procedia CIRP 55 (2016) : 176–81. http://dx.doi.org/10.1016/j.procir.2016.08.019.

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Dehtiarov, Ivan, Anna Neshta, Illia Kosov et Yaroslav Klok. « EXPERIMENTAL RESEARCH OF THE RIGIDITY OF FIXTURES WITH INCOMPLETE LOCATION FOR CONNECTING ROD TYPE PARTS ». Technical Sciences and Technologies, n^o 3(29) (2022) : 15–26. http://dx.doi.org/10.25140/2411-5363-2022-3(29)-15-26.

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The use of modern machining centers with wide technological capabilities and the active development of productions with a small-scale form of organization necessitates an increase in the efficiency of fixtures capable of ensuring sufficient accuracy of machining with minimal costs.Classical approaches to the design of fixtures do not always allow machining with one installation with high-performance cutting conditions, so it is necessary to move the new approaches that allow maximum tool availability, which is important for the competitiveness of enterprises.The analysis of research and publications on numerical modeling and experimental research on the processing of parts of a complex shape that have insufficient rigidity showed that the issues of static research of the stress-deformation state of fixtures with incomplete locating have received little attention in the scientific literature.The purpose of the article is to experimentally demonstrate the possibility of machining non-separable connecting rods in machine tools with incomplete basing and fastening only on unprocessed surfaces in one installation with the achievement of all the necessary indicators of dimensional accuracy.The work presents for the first time an improved fixture with an incomplete location for machining connecting rod-type parts, and experimental studies of its stress-strain state in static mode are performed. The determined values of stresses and displacements compared with the previously proposed machine tool showed its technical advantage in bearing capacity for loads acting during machining.In this work, it was experimentally proven for the first time that the design of the improved fixture for machining connecting rods is capable of providing the necessary machining accuracy under static load and at the same time has a margin of accuracy thatexceeds the value of deformations by 1.5...2.5 times. The presented results and the positive experience of manufacturing a sample of a fixture can be used for its further research in a dynamic mode directly during machining, as well as for the design of technological equipment for parts of other classes, using an approach that involves incomplete locating of the workpiece

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Sallese, Lorenzo, Niccolò Grossi, Antonio Scippa et Gianni Campatelli. « Numerical investigation of chatter suppression in milling using active fixtures in open-loop control ». Journal of Vibration and Control 24, n^o 9 (14 septembre 2016) : 1757–73. http://dx.doi.org/10.1177/1077546316668686.

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Among the chatter suppression techniques in milling, active fixtures seem to be the most industrially oriented, mainly because these devices could be directly retrofittable to a variety of machine tools. The actual performances strongly depend on fixture design and the control logic employed. The usual approach in the literature, derived from general active vibration control applications, is based on the employment of adaptive closed-loop controls aimed at mitigating the amplitude of chatter frequencies with targeted counteracting vibrations. Whilst this approach has proven its effectiveness, a general application would demand a wide actuation bandwidth that is practically impeded by inertial forces and actuator-related issues. This paper presents the study of the performance of alternative open-loop actuation strategies in suppressing chatter phenomena, aiming at limiting the required actuation bandwidth. A dedicated time-domain simulation model, integrating fixture dynamics and the features of piezoelectric actuators, is developed and experimentally validated in order to be used as a testing environment to assess the effectiveness of the proposed actuation strategies. An extensive numerical investigation is then carried out to highlight the most influential factors in assessing the capability of suppressing chatter vibrations. The results clearly demonstrated that the regenerative effect could be effectively disrupted by actuation frequencies close to half the tooth-pass frequency, as long as adequate displacement is provided by the actuators. This could sensibly increase the critical axial depth of cut and hence improve the achievable material removal rate, as discussed in the paper.

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Papastathis, T., O. Bakker, S. Ratchev et A. Popov. « Design Methodology for Mechatronic Active Fixtures with Movable Clamps ». Procedia CIRP 3 (2012) : 323–28. http://dx.doi.org/10.1016/j.procir.2012.07.056.

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Sallese, Lorenzo, Antonio Scippa, Niccolò Grossi et Gianni Campatelli. « Investigating Actuation Strategies in Active Fixtures for Chatter Suppression ». Procedia CIRP 46 (2016) : 311–14. http://dx.doi.org/10.1016/j.procir.2016.04.073.

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Fehlberg, Mark A., Ilana Nisky, Andrew J. Doxon et William R. Provancher. « Improved Active Handrest Performance Through Use of Virtual Fixtures ». IEEE Transactions on Human-Machine Systems 44, n^o 4 (août 2014) : 484–98. http://dx.doi.org/10.1109/thms.2014.2321531.

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Mann, Steve. « Intelligent Bathroom Fixtures and Systems : EXISTech Corporation's Safebath Project ». Leonardo 36, n^o 3 (juin 2003) : 207–10. http://dx.doi.org/10.1162/002409403321921424.

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EXISTech Corporation's computer networks, control systems and image-sensor technology facilitate hygienic touchless control of plumbing fixtures. Two of EXISTech's sensors are described here in detail: an active infrared faucet sensor and a passive infrared autoflush sensor. These devices allow internetworked plumbing systems to help facility managers and law-enforcement personnel remotely monitor the operation of bathroom fixtures. Intelligent fixtures and systems based on quantimetric sensing technology enhance the privacy of law-abiding users by eliminating the need for invasive policing of restrooms. New computer-vision algorithms also automatically detect accidents, as well as vandalism and contraband disposal, to assist remote monitoring by law enforcement.

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Parlato, Aldo, Elio Tomarchio, Cristiano Calligaro et Calogero Pace. « The methodology for active testing of electronic devices under the radiations ». Nuclear Technology and Radiation Protection 33, n^o 1 (2018) : 53–60. http://dx.doi.org/10.2298/ntrp1801053p.

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The methodology, developed for active testing of electronic devices under the radiations, is presented. The test set-up includes a gamma-ray facility, the hardware board/fixtures and the software tools purposely designed and realized. The methodology is so wide-ranging to allow us the verification of different classes of electronic devices, even if only application examples for static random access memory modules are reported.

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Erdem, Ilker, Gauti Asbjörnsson et Henrik Kihlman. « Workpiece force and position control for active and flexible fixtures in assembly ». International Journal of Advanced Manufacturing Technology 112, n^o 1-2 (19 novembre 2020) : 333–46. http://dx.doi.org/10.1007/s00170-020-06317-3.

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Savelkaev, Sergei V. « UNIVERSAL COAXIAL-STRIPLINE AND PROBE TEST FIXTURES AND THEIR CALIBRATION METHODS ». Vestnik SSUGT (Siberian State University of Geosystems and Technologies) 25, n^o 4 (2020) : 229–37. http://dx.doi.org/10.33764/2411-1759-2020-25-4-229-237.

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The design and calibration method for a coaxial-stripline test fixture that provides connection of microwave circuit analyzer of both coaxial measures and microstrip calibrators, as well as the active components under study, such as transistors, are considered. The test fixture provides high repeatability of connecting coaxial measures, microstrip calibrators, and active components being studied and has a small standing-wave ratio and loss. The test fixture is calibrated with using a minimal set of easily calculated microstrip calibrators with low losses, which, taking into account the high repeatability of their connection, reduces the complexity of its calibration and increases the accuracy of transmitting measurement results from the coaxial line to the microstrip line. The possibility of transmitting measurement results from the coaxial line to the microstrip line extends the scope of the State System for Ensuring the Uniformity of Measurements to the microstrip line. The design of the probe test fixture and a method of its calibration by a specialized microstrip calibrator are also given.

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Neitmann, Maximilian, Tom Rothe, Erik Kappel et Christian Hühne. « Assembly of Compliant Structures with Autonomous Industrial Mobile Manipulators (AIMM) Using an End Effector with Active Deformation Compensation for the Assembly of Flaps ». Machines 10, n^o 5 (21 avril 2022) : 291. http://dx.doi.org/10.3390/machines10050291.

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Composite structures in aeroplanes are often thin-walled and lightweight, resulting in significant compliance, which presents a handling and assembly challenge due to the associated part deformations. In order to counteract these deformations, the parts are held in their specified geometry using stiff and correspondingly heavy fixtures or jigs. Mobile industrial robots are very versatile and widely used in industrial volume production, but they are limited in their payload capacity. High-rate production of large aerospace modules requires highly automated flexible assembly processes. The approach presented in this paper is to combine mobile units with lightweight assembly jigs that have the capability of deformation compensation. The subject of the study is a high-rate assembly process for flap modules using an Autonomous Industrial Mobile Manipulator (AIMM) and a lightweight end effector. The end effector has a shape compensation function, implemented by an integrated Stewart platform, which enables the compensation of manufacturing tolerances as well as gravity effects. The compensation function is used in a closed loop and counteracts shape deviations by appropriate fixture shape adjustments. The paper reports on the conceptual design of the assembly scenario, the design of the end effector, its realization and the successful experimental demonstration at 1:1 scale.

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Shrivastava, A., et A. Verma. « Implementation of Improved Jigs and Fixtures in the Production of Non-Active Rotary Paddy Weeder ». Science, Technology and Arts Research Journal 3, n^o 4 (10 février 2015) : 152. http://dx.doi.org/10.4314/star.v3i4.22.

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Akanmu, A., C. Anumba et J. Messner. « Active Monitoring and Control of Light Fixtures during Building Construction and Operation : Cyber-Physical Systems Approach ». Journal of Architectural Engineering 20, n^o 2 (juin 2014) : 04013008. http://dx.doi.org/10.1061/(asce)ae.1943-5568.0000140.

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LUNDBORG, G., P. I. BRÅNEMARK et I. CARLSSON. « Metacarpophalangeal Joint Arthroplasty Based on the Osseointegration Concept ». Journal of Hand Surgery 18, n^o 6 (décembre 1993) : 693–703. http://dx.doi.org/10.1016/0266-7681(93)90224-4.

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The osseointegration concept has been used for fixation of 68 MP joint endoprostheses in 31 patients operated on at the Department of Hand Surgery, Malmö General Hospital during the period 1988–1992. The indications were rheumatoid arthritis (50 joints), primary osteoarthrosis (three joints), post-traumatic osteoarthrosis (three joints), post-traumatic osteoarthrosis (five joints), post-infectious osteoarthrosis (seven joints) and joint deformities secondary to spastic conditions (three joints). The average follow-up time was 2.5 years (6–54 months). The surgical procedure included resection of the joint followed by introduction of screw-shaped titanium fixtures into the bone marrow cavities of the metacarpal and the phalangeal base. Rheumatoid cases usually required grafting of cancellous bone and marrow from the iliac crest. At the same time a flexible constrained silicone spacer was connected to the titanium fixtures in such a way as to allow later replacement of the spacer if accessory. The average active range of motion (ROM) was 57° in the rheumatoid cases and 50° in all cases. Radiological and clinical osseointegration occurred in every case, and there were no clinical signs of loosening. In four cases (6%) there was a fracture of the joint mechanism. Patient satisfaction was high, with pain relief, increased range of motion, improved hand function and good cosmetic appearance.

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Yoshikawa, Tsuneo. « Passive and Active Closures by Constraining Mechanisms ». Journal of Dynamic Systems, Measurement, and Control 121, n^o 3 (1 septembre 1999) : 418–24. http://dx.doi.org/10.1115/1.2802490.

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This paper provides a unified theoretical framework for analytical characterization of grasping and manipulation capability of robotic grippers and hands as well as fixing capability of fixtures and vises. The concept of passive closure and active closure for general constraining mechanisms consisting of fixed and/or articulated constraining limbs is introduced. These concepts are useful for explicitly distinguishing the two kinds of capabilities of the constraining mechanism: Passive closure represents the ability of fixing devices and active closure represents the ability of manipulating devices. Passive closure is further classified into passive form closure and passive force closure. Passive form closure is essentially the same as Reuleaux’s classical form closure and passive force closure is a substantial generalization of classical force closure to the case where articulated constraining limbs exist. Conditions for these closures to hold are studied. After a brief review of conditions for passive form closure, several conditions for passive force closure are given. One outcome is that, under the assumption that the contact points are frictionless and the active contact points are independent, for the existence of passive force closure there must be at least six (three) fixed contact points and one active contact point in the case of three-dimensional (two-dimensional, respectively) space. Finally, a necessary and sufficient condition for active closure is given for the case of frictional point contacts by constraining limbs with enough degrees-of-freedom. This condition consists of a general positioning condition of contact points and the existence condition of nonzero internal force. This condition has a quite natural physical interpretation.

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Trojano, Max L., Garrett Rucker et Brian McGillen. « Using Standardized Whiteboards to Improve Patient Engagement ». Journal of Patient Experience 9 (janvier 2022) : 237437352211030. http://dx.doi.org/10.1177/23743735221103030.

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Whiteboards are ubiquitous fixtures in hospital rooms that may represent a ready-made patient engagement tool; yet, their use has only been minimally explored. This study examined the relationship between a standardized whiteboard communication process and patient activation by using the Patient Activation Measure (PAM®). Participants ( N = 172) that were optimally involved in whiteboard communication had significantly higher PAM® scores compared to those who were suboptimally involved. PAM® scores also correlated with self-reported role, with those endorsing active participation scoring higher than passive listeners. Accordingly, this study establishes a positive association between the structured use of whiteboards and patient activation.

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Sanz-Calle, Markel, Zoltan Dombovari, Jokin Munoa, Alexander Iglesias et Luis Norberto López de Lacalle. « Self-Tuning Algorithm for Tuneable Clamping Table for Chatter Suppression in Blade Recontouring ». Applied Sciences 11, n^o 6 (13 mars 2021) : 2569. http://dx.doi.org/10.3390/app11062569.

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The production and repair of blades for aerospace engines and energy turbines is a complex process due their inherently low stiffness and damping properties. The final recontouring operation is usually performed by milling operations where regenerative chatter is one of the main productivity limiting factors. With the objective of avoiding specific stiffening fixtures for each blade geometry, this paper proposes a semi-active tuneable clamping table (TCT) based on mode tuning for blade machining. The active mode of the device can be externally controlled by means of a rotary spring and eddy current damping modules. Its in-series architecture allows damping to be introduced to the critical mode of the thin-walled part without any direct contact in the machining area and enables a more universal clamping. Its chatter suppression capabilities are maximized by means of a novel self-tuning algorithm that iteratively optimizes the tuning for the measured chatter frequency. The benefits of the iterative algorithm are validated through semidiscretization and initial value time-domain simulations, showing a clear improvement in blade recontouring stability compared to regular broad-bandwidth tuning methods.

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Mohammadi, Bijan, et Ehsan Anbarzadeh. « Evaluation of Viability and Cell Proliferation in Bone and Gingival on Dental Implant Fixtures with Active Sandblasted and Sandblasted Surfaces by the Cytotoxicity Test Method ». Journal of Biomimetics, Biomaterials and Biomedical Engineering 56 (20 mai 2022) : 165–72. http://dx.doi.org/10.4028/p-gmmc8m.

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In recent years, the technology of dental implants has advanced a lot and this has become one of the main reasons for dentists to refer to implants immediately after tooth extraction. Evaluation of cell survival in implantology studies to determine cell sensitivity determines the outcome of treatment. This study aimed to investigate the bone integration properties as well as the cytotoxicity between the implant surface and the jaw bone. In this study, cytotoxicity test was used to evaluate the toxicity and viability of sandblasted large grit acid etched, and sandblasted large grit acid etched active surfaces in 3A brand dental implants with G292 osteoblastic cells and human gingival fibroblasts cells are discussed. This operation was performed using a laboratory incubator of the German company MEMMERT for 24 hours, by neubauer lam cells counting for one hundred thousand cultured cells in each test at a temperature of 37 °C, a pressure of 1 atmosphere and 90% humidity. Based on the scanning electron microscopy images and the cytotoxicity test results, it can be seen that the bone graft of the implant, with the sandblasted large grit acid etched active surface treatment, is much better and also one week faster than the implant with the sandblasted large grit acid etched one. However, the viability of the implant with the sandblasted large grit acid etched active surface treatment for both G292 osteoblastic cells and human gingival fibroblasts cells samples was equal to 98.4% and 97.3%, respectively, and is lower than the sandblasted large grit acid etched surface treatment. The results show that the viability of the sandblasted large grit acid etched implant is about 1.5 to 2% higher than the sandblasted large grit acid etched active one, but the surface integrity of sandblasted large grit acid etched active is better than sandblasted large grit acid etched in all samples, and the treatment process is reduced by one week.

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Havrlík, Matouš, Martin Libra, Vladislav Poulek et Pavel Kouřím. « Analysis of Output Signal Distortion of Galvanic Isolation Circuits for Monitoring the Mains Voltage Waveform ». Sensors 22, n^o 20 (13 octobre 2022) : 7769. http://dx.doi.org/10.3390/s22207769.

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Different methods for galvanically isolated monitoring of the mains voltage waveform were evaluated. The aim was to determine the level of distortion of the output signal relative to the input signal and the suitability of each method for calculating active power values. Six fixtures were tested: two voltage transformers, an electronic circuit with a current transformer, a standalone current transformer, a simple circuit with optocouplers, and a circuit with an A/D-D/A converter with capacitive coupling. The input and output waveforms were mathematically analyzed by three methods: (1) calculating the spectral components of waveforms and the relative changes in their THD (total harmonic distortion) values, (2) determining the similarity of waveforms according to the size of the area bounded by the input and output waveform curves, and (3) determining the accuracy of the active power calculation based on the output waveform. The time difference in the zero crossing of the input and output signals was measured, and further calculations for the second and third method were performed on the zero-crossing time shift-corrected waveforms. Other aspects of selecting the appropriate type of monitoring element, such as power consumption or overall circuit complexity, were also evaluated.

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Topolianskii, P. A., S. A. Ermakov et A. P. Topolianskii. « PRECISION AND CONFIDENCE LEVEL OF CHANGES IN MEASUREMENTS OF GAS ANALYTICAL COMPLEXES BY MEANS OF APPLYING INERT COVERS ON GAS TRACT ELEMENTS ». Kontrol'. Diagnostika, n^o 275 (mai 2021) : 4–13. http://dx.doi.org/10.14489/td.2021.05.pp.004-013.

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The relevance of using inert (barrier) nanocoatings for protection (passivation) of parts made of stainless steel has been considered. Such coatings ensure solving problems related to the precision and accuracy of the assay and quality testing of substances with the minimum content of active compounds in a sample, lack of stability in the content of active compounds in a sample over time, inability to treat large amounts of samples without repeated calibration. The findings of the research into the new inert SilcoPateks coating applied by plasma assisted chemical vapor deposition (PACVD process) have been presented. Such coating is used for protection against chemically active substances capable of absorbing and interacting with metals, of changing the sample composition, for countering sulfide and other corrosion. We present a comparative analysis of the SilcoPateks coating with its close analogues – SilcoNert® and DurSan® coatings developed by the world’s leading companies – the Restek Co. and SilkoTek Co. (USA). The SilcoPateks coating is widely used in the domestic equipment for chromatography, mass spectrometry, in ultraviolet fluorescent and other analyzers of substances, in samplers for storage, for transportation, testing and research of samples of substances, for stainless fixtures (valves, faucets), fittings and manometers, for sampling stands, air conditioning systems, calibration panels, coolers for cooling samples, water-oil traps (filters) and other items.

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Sampathkumar, Priya, Debra Apenhorst, Al Kubly, Mark Keller et Alan Wright. « Blackwater Event : Water Management and Remediation at a Major Medical Center ». Infection Control & ; Hospital Epidemiology 41, S1 (octobre 2020) : s140. http://dx.doi.org/10.1017/ice.2020.655.

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Background: The CMS and the CDC recommend that all healthcare facilities have an effective water management program (WMP). Our WMP has been in place since 2010; it includes members from facilities operations, infection prevention and control, environmental services, and industrial hygiene. The team meets regularly to discuss current water issues, reviews validation data and water testing reports. Description of event: In April 2018, we suddenly experienced discolored water and sediment at multiple water fixtures throughout the 3.3 million square-foot hospital campus. The hospital incident command structure (HICS) was activated to assist in investigating and managing the situation. Immediate response: Water was deemed unsafe while the cause was being investigated. Bottled water was distributed to 950 hospital patients, and >8,000 staff and visitors. The impact included alternative methods for hand hygiene, the use of bottled water for food preparation and drinking, and the elimination of showers for patients and staff. The dialysis unit used an independent water supply that was not affected. Investigation and remediation: The hospital had 2 sources of domestic cold water: municipal water and a private well that had been in use since 1912. An investigation revealed that the well pump had malfunctioned, drawing gravel into the potable water supply. This overwhelmed the plumbing, blocked toilets and likely dislodged biofilm from the pipes. Early testing showed high levels of corrosion byproducts (ie, iron, copper, and lead) and bacterial contamination in the water, including presence of Legionella. Remediation involved isolating the well, switching to municipal water as the sole source of potable water, flushing the system, and retesting. Overall, 105 technicians flushed the water system including 6,000 water fixtures, 125 drinking fountains, and 95 emergency showers and eyewashes; they sanitized and cleaned 130 ice machines and tested 240 backflow preventers. We retested 437 water samples after remediation; all parameters had returned to the normal range. The existing water process flow diagrams were used to guide sampling for water testing. Conclusions: The hospital’s water system was brought back on line in 78 hours after the first report of “black water.” An active, mature WMP with multiple facilities technicians trained in water sampling enabled a quick response. Coordination through the HICS structure streamlined the response and enabled clear communication throughout the process.Funding: NoneDisclosures: None

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Kibrit, Gunay, Fahriye Altinay, Gokmen Dagli, Zehra Altinay, Ramesh Sharma, Rustam Shadiev, Ahmed Tlili, Menil Celebi, Mohamed Jemni et Meryem Bastas. « Evaluation of Sustainability and Accessibility Strategies in Vocational Education Training ». Sustainability 14, n^o 19 (23 septembre 2022) : 12061. http://dx.doi.org/10.3390/su141912061.

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Sustainability plays a significant role in all levels of education. Paying attention to strategies for accessibility in educational levels is highly needed. This research aims to evaluate accessibility strategies in vocational education training (VET). It is significant to put efforts into VET to raise awareness on accessibility for the societal benefits of inclusivity and digital transformation in services for all. While preparing the educational context for digital education, accessibility strategies are essential for establishing the future of education. The study adopted the qualitative research approach and used semi-structured interviews and public reports for data collection. The sample of the study comprised the staff working at the management/administrative level in VET and at the ministry of education. Results indicated that suitable strategies are crucial for sustainability and accessibility in VET. Active citizenship for the global world requires understanding the practical sides of accessibility. In this respect, this study recommends vocational training activities based on sustainability and accessibility. To set sustainable strategies in VET, defining the proper roles and responsibilities of teachers, trainers, and staff are essential. The administrative authority, protection of school fixtures and procedures, resolving financial issues, overcoming obstacles such as quality activities, and the professional inadequacy of teacher training are basic steps for developing VET.

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Brown, Andrew D., Nathaniel Greene, David J. Audet, Caylin R. McCallick, Carol A. Sammeth, David A. Anderson, Gregory T. Rule et Theodore F. Argo. « Quantifying impacts of hearing protection devices on sound localization in azimuth and elevation : Toward predictors of performance ». Journal of the Acoustical Society of America 151, n^o 4 (avril 2022) : A224. http://dx.doi.org/10.1121/10.0011131.

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Modern hearing protection devices (HPDs) effectively mitigate the risk of noise-induced hearing loss when used as intended, and some even preserve the audibility of low-to-moderate-intensity sounds. Nonetheless, negative auditory perceptual side-effects continue to limit usability in critical settings. Most notably, dozens of studies have shown that HPDs lead to significant errors in sound source localization. Several studies have specifically linked such errors to HPD-induced distortions of the spectra of transmitted signals. Here we provide an update on a multi-site study designed to capture patterns in sound localization errors (among other impacts) across different classes of HPDs, toward validation of acoustic predictors of HPD performance. At two independent study sites, human listeners localized brief broadband signals with open ears (control) and during use of passive and active earplug and earmuff-style devices. Sources spanning 360° in azimuth and −30° to + 60° in elevation enabled measurement, via wireless head-tracking, of 2-D localization error across a broad range of source locations. New metrics integrating these measurements with acoustic data, obtained via standardized HPD test fixtures as well as in-ear microphones designed to capture individual variation in HPD impacts, will support application-specific selection of existing HPDs and inform the design of new HPDs.

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Hamzah, Hanafi, Muhammad Shahrim Ab Karim, Yuhanis Abd Aziz et Azilah Kasim. « Environmental awareness, initiatives and performance in the small- and medium-scale enterprise hotel industry of Malaysia ». Journal of Emerging Economies and Islamic Research 8, n^o 1 (31 janvier 2020) : 43. http://dx.doi.org/10.24191/jeeir.v8i1.7700.

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This paper examines the environmental awareness, initiatives and performance in the Malaysia Small- and Medium-Scale Enterprise (SME) hotel industry revealing that most hotel managers actively introduce initiatives that contribute to cost savings. The main purpose of this paper aims to examine the environmental awareness, initiatives and performance in Malaysia SME hotel industry. A mixed research method was adopted involving quantitative surveys with 252 hotels in Malaysia and 11 face-to-face interviews with the selected hotel managers, facilities managers and engineers. Responses from the surveys and interviews with 252 managers show that SME hotels in Malaysia have a high level of environmental awareness. Most hoteliers actively introduce initiatives that contribute to cost savings. Initiatives including using energy conservation light bulbs, having an active system to detect/repair lacking facilities and installing water conserving fixtures are widely implemented, while programs involving using solar lawn light, recycling leftover food and reusing wastewater. Major barriers for going green include the lack of government regulations on environmental management systems (EMS), financial constraints, the lack of employees to handle EMS and the fear that environmental initiatives may negatively impact the guest’s experience, especially customers who expect enjoying the luxuries services in Malaysia hotels. Lower star hotels experience more difficulties in adopting green approaches. This paper presents a single case study of Malaysia; therefore, the results in this research may have limited generalizability.

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Wang, Mei, et Zheng Long Wang. « Design of Clamping Fixture for Active Fixing-Board Used in Vibration Experiment ». Applied Mechanics and Materials 456 (octobre 2013) : 567–70. http://dx.doi.org/10.4028/www.scientific.net/amm.456.567.

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Clamping fixture of active fixing-board plays an important role on vibration experiment. In this paper, the clamping fixture for active fixing-board is designed based on fixture theory. Modal characteristic of the fixture designed is analyzed using finite element software ANSYS. Research shows that the requirement of the vibration experiment on active fixing-board can be met completely by the fixture designed in this paper.

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Ma, Junkun, Keith Coogler et Minjae Suh. « Inquiry-based learning : Development of an introductory manufacturing processes course based on a mobile inverted pendulum robot ». International Journal of Mechanical Engineering Education 48, n^o 4 (1 mai 2019) : 371–90. http://dx.doi.org/10.1177/0306419019844257.

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This paper describes the development of an innovative introductory manufacturing processes course designed to expose students to a broad overview of fundamental concepts, methods, procedures, tools, and equipment used in the manufacturing industry. Based on an educational mobile inverted pendulum robot, students are introduced to product design and prototyping by identifying an existing problem with a component in the robot, redesigning the component using computer aided design software, and then building a prototype using additive manufacturing methods. Subsequently, a set of hypothetical design requirement changes is imposed, and various design methods and manufacturing processes that can be used to make components to satisfy these new requirements are discussed. Topics covered include integrated product design, additive manufacturing prototyping based on different technologies, plastic injection molding, sand casting, and fundamentals of both computer aided manufacturing and computer numerical control machining. Tools, fixtures, and accessories required in these processes, as well as associated challenges, are also discussed. This course adapts the inquiry-based learning active learning pedagogical approach and focuses on the development of students’ ability to conduct analytical analysis and to apply a knowledge of mathematics, science, engineering, and technology to solve practical engineering technology problems. As an introductory course designed to be offered to freshman level students, this course engages students in engineering technology related topics and stimulates their interest in manufacturing related subjects. It helps with improving the engineering student retention rate and serves as a pathway connecting students to more advanced specialized manufacturing courses such as computer numerical control machining technology. This paper presents course materials developed and student feedback as well as their evaluation of the course effectiveness based on a summative questionnaire-style survey from the first cohort of students.

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Wan, Yim King Penny, Sow Hup Joanne Chan et Hui Lan Wendy Huang. « Environmental awareness, initiatives and performance in the hotel industry of Macau ». Tourism Review 72, n^o 1 (18 avril 2017) : 87–103. http://dx.doi.org/10.1108/tr-06-2016-0016.

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Purpose This paper aims to examine the environmental awareness, initiatives and performance in the Macau hotel industry. Design/methodology/approach A mixed research method was adopted involving quantitative surveys with 31 hotels in Macau and 11 face-to-face interviews with the hotel managers, facilities managers and engineers. Findings Response from surveys and interviews with 31 hoteliers show that hotels in Macau have a high level of environmental awareness. Most hoteliers actively introduce initiatives that contribute to cost savings. Initiatives including using energy conservation light bulbs, having an active system to detect/repair leaking facilities and installing water conserving fixtures are widely implemented, while programs involving using solar lawn light, recycling leftover food and reusing wastewater are not. Major barriers for going green include the lack of government regulations on environmental management (EM), financial constraints, the lack of employees to handle EM and the fear that environmental initiatives may negatively impact the guest’s experience, especially those VIP and hardcore gamblers and customers who expect enjoying the luxuries services in Macau hotels. Lower star hotels experience more difficulties in adopting green approaches. Research limitations/implications This paper presents a single case study of Macau; therefore, the results in this research may have limited generalizability. Originality/value This paper is one of the very few attempts that investigate EM in Macau – a renowned world tourism and gambling destination, where the vast majority of hotels have their casino facilities. Results show that apart from the financial consideration and the lack of government enforcement to adopt green measures similar to hotels in other destinations, EM practices of Macau’s hotels are also constrained by its customer base and the acute shortage of human resources that is caused by the tourism boom.

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Kicha, Ekaterina, Vadim Mikhailenko, Dmitriy Malovik et Maksim Kicha. « METHOD OF FILLING ELECTRONIC PRODUCTS WITH VIKSINT U-1-18 SEALANT ». Electrical and data processing facilities and systems 18, n^o 1 (2022) : 143–53. http://dx.doi.org/10.17122/1999-5458-2022-18-1-143-153.

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Relevance The operating conditions of modern electronic products require a responsible approach to their protection from aggressive environmental influences. The use of imported materials in the production of special equipment is limited, so technologists are forced to look for effective ways to work with domestic materials, many of which were developed in the middle of the twentieth century. The use of Viksint U-1-18 sealant has not lost its relevance, it is widely and effectively used. Aim of research To offer an effective and ready-to-use method for pouring metal joints made of stainless steels, aluminum and titanium alloys, for sealing equipment operating in air at temperatures from minus 60 °C to 300 °C when exposed to vibrations — a method that does not require the use of advanced technological equipment. Research methods Review and analysis of normative and technical documentation and scientific literature, as well as generalization of experience in the use of organosilicon sealants by instrumentmaking and shipbuilding enterprises. Results A method has been developed for pouring the product with Viksint U-1-18 sealant. Documentation on the application of the method includes the following sections: — general provisions; — lists of basic and auxiliary materials, equipment, tools and fixtures; technological operations; — characteristics of the main materials (sealant «Viksint U-1-18», sealing paste U-1, catalyst No. 18, sublayer P 11, water-repellent liquid 136-41, active alumina); — safety precautions (indicating the toxic properties of the materials used and indicators of their fire and explosion hazard). Technological operations include: — preparation of products for pouring; — preparation of sealant «Viksint U-1-18» and paste No. 2; — filling products with sealant; — technical control. The proposed method is intended for small enterprises, workshops and laboratories for which the purchase of expensive technological equipment is unprofitable. The results of this work can be used as a reference tool by specialists of design bureaus and manufacturing enterprises, as well as labor protection units, including for the development of organization standards.

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Rice, Emily M., et Joao H. C. Costa. « PSXVI-20 Real-time localization system for dairy cattle in a commercial facility : Evaluation of dynamic positioning ability ». Journal of Animal Science 99, Supplement_3 (8 octobre 2021) : 221–22. http://dx.doi.org/10.1093/jas/skab235.403.

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Abstract Real-time location tracking of dairy cattle on commercial facilities enables producers to quickly locate and tend to cows and provides insight into health status and animal welfare. The effectiveness of these systems depends on accurate and reliable reporting of information. Therefore, this experiment’s objective was to assess the dynamic positioning abilities of a commercially available real-time location ear tag system (SmartBow; Zoetis, Parsippany, NJ) for use in group-housed dairy cattle. Using 2 pens of a freestall barn, cameras (n = 18) were installed on barn fixtures and positioned to photograph cow usage of feedbunk (n = 4), stall (n = 10), or waterer (n = 4). Photographs were captured automatically at 1-min intervals for 85 hours, consecutively. Laser measurements determined X and Y coordinates for reference point locations respective to camera. In dynamic position assessments, variations in ear tag proximity to measured reference points are to be expected. One trained observer reviewed photographs, saving only those depicting cows with visible farm-assigned ID. Data points were only defined if farm-assigned ID was associated with an active technology ear tag. For data analyses, technology-reported X and Y coordinates of data points were compared to reference point locations. Of all data points (n = 114,633), mean distance error was 3.82 m (SD= 6.73 m). Median distance error was 2.44 m (SD= 6.73; Q1= 1.41 m; Q3=5.13 m). With removal of outliers (99th percentile), data (n = 113,487) had a mean distance error of 3.82 m (min= 0.01 m; max= 33.80 m) and a median of 2.41 m (SD= 2.78 m; Q1= 1.40 m; Q3= 4.95 m). Using distance error, mean percentages of data points that fell within specified radii of circles centered about reference point locations were calculated (Table 1). These results suggest that this ear tag technology can accurately report the dynamic positions of dairy cattle moving freely in a commercial freestall barn environment.

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Shpak, S., V. Martirosova, T. Sakhno et G. Kozhushko. « DIRECTIONS FOR IMPROVEMENT OF STANDARDS ON LED TECHNIQUE AND LIGHTING WITH ITS USE ». Municipal economy of cities 1, n^o 154 (3 avril 2020) : 57–66. http://dx.doi.org/10.33042/2522-1809-2020-1-154-57-66.

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One of the main tasks of high-quality lighting is to provide comfortable visual work and adequate perception of illuminated objects by obtaining light with a wide range of correlated color temperatures with high color rendering quality. The paper analyzes the shortcomings of national regulatory documents on establishing tolerances for the color of lamps and fixtures using LEDs and evaluating their quality in color reproduction. Instead of using Mac Adam ellipses on the SIE 1931 (x, y) color chart for establishing the color requirements it is recommended to use circles on the 1976 SIE (u ', v'), and evaluate the color rendering quality using the CRI method, additionally apply the CQS and TM 30-18 methods. Due to the fact that the spatial color of LED luminaires can be inhomogeneous, it is recommended to indicate both the average color and color in a certain direction, as well as an indicator of the color heterogeneity. The necessity of developing standards for protection against unwanted non-visual biological effects, as well as other negative effects of artificial light, in particular, excessive brightness, pulsation of the light flux, photobiological hazards, etc., is substantiated. Considering the importance of the influence of light pulsation on the quality of lighting, before the development of CIE or IEC standards, it is recommended that national standards for LED lamps and luminaires include the requirements for description of pulsation parameters and measurement methods in accordance with the recommendations of IEEE 1789-2015 standard, which is the most advanced today. For the design of ergonomic lighting, it is proposed to provide information on lamps and luminaires related to their maximum brightness. When developing new criteria for lighting, taking into account the visual impact, it is already possible to use the knowledge accumulated by this time, in particular, for creation of biologically active and biologically dimmed light by changing the spectral composition of radiation and illumination. Proposals related to the limits of the correlated colour temperature, brightness, level of pulsation for lighting of children and educational institutions, residential premises and the like are also considered. Recommendations on the development of new national standards of Ukraine harmonized with international ones are also provided. Keywords: сolor rendering index, percent flicker, correlated colour temperature, illumination, photobiological safety

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Jia, Jiao, Yingmin Jia et Shihao Sun. « Design and analysis of an active gimbal simulator with three degrees-of-freedom for ground testing ». Proceedings of the Institution of Mechanical Engineers, Part C : Journal of Mechanical Engineering Science 233, n^o 7 (12 juillet 2018) : 2552–62. http://dx.doi.org/10.1177/0954406218787838.

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In this paper, a new active gimbal simulator is developed for testing the attitude determination and control system of satellites. The active gimbal simulator is composed of a rolling joint, a pitching joint, a main support frame, an active yawing joint, and a fixture. The rolling joint enables the active gimbal simulator to be applied to the columnar satellite without the fixture. The contact forces between the rolling joint and the test satellite (or the fixture) can be regulated by the support of the pitching joint. The object attached to the active gimbal simulator is at neutral equilibrium and can maintain balance at an arbitrary attitude. Hence, the object can rotate freely without being affected by its gravity. The active gimbal simulator is an approximately free-to-free suspension or support method. Compared with the traditional gimbals, the active gimbal simulator can be applied to objects of arbitrary shape especially cylinders and the effect of exogenous mass and inertia introduced by the connection mechanism is reduced. The design parameters of the active gimbal simulator are optimized based on the force analysis. A specific prototype was made, and its feasibility was verified by laboratory-based experiments.

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YAMAGUCHI, Tomomi, Masahiro HIGUCHI, Yoshikazu FUKUTANI et Kiyoshi NAGAI. « Development of Active Flexible Fixture for Assembly (1st Report) ». Journal of the Japan Society for Precision Engineering, Contributed Papers 71, n^o 12 (2005) : 1563–67. http://dx.doi.org/10.2493/jspe.71.1563.

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YAMAGUCHI, Tomomi, Naomichi FURUSHIRO et Masahiro HIGUCHI. « Development of Active Flexible Fixture for Assembly (2nd Report) ». Journal of the Japan Society for Precision Engineering 75, n^o 9 (2009) : 1134–38. http://dx.doi.org/10.2493/jjspe.75.1134.

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Северин, В. Д. « СУЧАСНЕ ОСВІТЛЕННЯ В ДИЗАЙНІ МУЗЕЙНИХ ЕКСПОЗИЦІЙ ». Humanities journal, n^o 2 (29 octobre 2018) : 89–98. http://dx.doi.org/10.32620/gch.2018.2.10.

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In modern design practice lighting plays an important role. Lighting means intensification of visual and psychological effect of museum exposition. Light plays an active role in perception of exhibit, revealing its shape, texture and color. Natural light is used to create a broad background, and artificial – to focus attention on specific information. The best way is the combination of artificial and natural light. This balance is possible due to technological achievement. New ways of lighting create the conditions for better preservation of objects.Lighting techniques give the possibility to make the exposure dynamic, without resorting to mechanical kinematic schemes. Since the motion of light attracts the attention of the viewer more than the movement of objects, this fact became the basis for development of a number of interesting schemes of dynamic lighting. Stands and showcases with dynamic illumination leave a brighter footprint in memory.The choice of the lighting system is closely linked with the architecture of the museum building and with the system of museum lighting (natural, artificial and combined). In this case, it is necessary to take into account the complexity of specifics of the museum exposition – the need to create the best illumination of exhibits and at the same time to protect them from the harmful effects of light rays. Lighting systems are based on the composition and properties of exhibited museum objects and the acceptable level of lighting for various categories of exhibits.Artificial lighting must be carried out mainly by sources of light, whose radiation in the spectrum is close to the daytime. For illumination special lighting fittings, which are usually hidden from visitors (behind suspended ceilings, embedded in furniture or exhibition equipment) should be used.Nowadays there is a wide arsenal of lighting means aimed to increase the visual and psychological effect of museum exposition, various types of lighting fixtures and lamps used to illuminate expositions. Among the lighting products, the leading role belongs to LED technologies. These technologies are characterized by qualities that are decisive in the organization of the museum environment. This is the ability to give white light to each exhibit, high light output at low power consumption, fire safety, the possibility of tape mounting of light sources, the implementation of programmable light scenarios with a change in color gamut. The latest technologies in lighting systems play an important role in design of museum exposition.

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Bakker, O. J., A. A. Popov, E. Salvi, A. Merlo et S. M. Ratchev. « Model-Based Control of An Active Fixture for Advanced Aerospace Components ». Proceedings of the Institution of Mechanical Engineers, Part B : Journal of Engineering Manufacture 225, n^o 1 (janvier 2011) : 35–51. http://dx.doi.org/10.1177/09544054jem2042.

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Cui, Jie, Alberto Behar, Willy Wong et Hans Kunov. « Insertion loss testing of active noise reduction headsets using acoustic fixture ». Applied Acoustics 64, n^o 10 (octobre 2003) : 1011–31. http://dx.doi.org/10.1016/s0003-682x(03)00067-7.

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Savel'kaev, S. V. « Improving the coaxial-stripline test fixture calibration process ». Metrologiya, n^o 2 (4 juillet 2021) : 20–30. http://dx.doi.org/10.32446/0132-4713.2021-2-20-30.

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The article is devoted to the improvement of the method of calibration of a coaxial-stripline test fixture. Its improvement ensures the transfer of the measurement planes of the S-parameters of the microwave active components, for example transistors, from the coaxial measuring path of the analyzer to the micro-strip line, what is important for designing microstrip devices for various purposes based on the measured S-parameters.

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Ebrahimpour, Reza, Rasul Fesharakifard et Seyed Mehdi Rezaei. « An adaptive approach to compensate seam tracking error in robotic welding process by a moving fixture ». International Journal of Advanced Robotic Systems 15, n^o 6 (1 novembre 2018) : 172988141881620. http://dx.doi.org/10.1177/1729881418816209.

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Welding is one of the most common method of connecting parts. Welding methods and processes are very diverse. Welding can be of fusion or solid state types. Arc welding, which is classified as fusion method, is the most widespread method of welding, and it involves many processes. In gas metal arc welding or metal inert gas–metal active gas, the protection of the molten weld pool is carried out by a shielding gas and the filler metal is in the form of wire which is automatically fed to the molten weld pool. As a semi-metallic arc process, the gas metal arc welding is a very good process for robotic welding. In this article, to conduct the metal active gas welding torch, an auxiliary ball screw servomechanism is proposed to move under a welder robot to track the welded seam. This servomechanism acts as a moving fixture and operates separately from the robot. At last, a decentralized control method based on adaptive sliding mode is designed and implemented on the fixture to provide the desired motion. Experimental results demonstrate an appropriate accuracy of seam tracking and error compensation by the proposed method.

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Sallese, Lorenzo, Giacomo Innocenti, Niccolò Grossi, Antonio Scippa, Roberto Flores, Michele Basso et Gianni Campatelli. « Mitigation of chatter instabilities in milling using an active fixture with a novel control strategy ». International Journal of Advanced Manufacturing Technology 89, n^o 9-12 (15 décembre 2016) : 2771–87. http://dx.doi.org/10.1007/s00170-016-9831-6.

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Gruijthuijsen, Caspar, Gianni Borghesan, Dominiek Reynaerts et Emmanuel Vander Poorten. « A Hybrid Active/Passive Wrist Approach for Increasing Virtual Fixture Stiffness in Comanipulated Robotic Minimally Invasive Surgery ». IEEE Robotics and Automation Letters 4, n^o 3 (juillet 2019) : 3029–36. http://dx.doi.org/10.1109/lra.2019.2923950.

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Wu, Xiaolin, Xiaodong Li, Jinqiu Sang et Xiaobin Cheng. « A comparison of methods to measure the sound attenuation of active noise reduction hearing protectors ». Journal of the Acoustical Society of America 151, n^o 4 (avril 2022) : A217. http://dx.doi.org/10.1121/10.0011098.

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Hearing protectors equipped with active noise reduction (ANR) functions have become popular and widespread in recent years. It is important to assess the sound attenuation performance of the ANR hearing protectors properly, which remains a problem. This work studies several typical measurement methods, including the real-ear attenuation at threshold (REAT), microphone in real-ear (MIRE), and the acoustic test fixture (ATF). In order to reduce the masking effect from the noise generated from the ANR electronic system when ANR is turned on during the REAT test, a modified tone sound instead of one-third octave band noise is used as the test signal. The results obtained from the different measurement methods on several ANR headphones and earphones are compared and the differences are discussed. It is found that the measurement differences among those methods are huge. The values of active insertion loss measured by the REAT method are much lower than those assessed by the MIRE procedure. This work contributes to the development of the test methods to assess the sound attenuation of the ANR hearing protectors.

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Sun, Tianyu, Lei Qiao et Mingjun Xia. « Effective Failure Analysis for Packaged Semiconductor Lasers with a Simple Sample Preparation and Home-Made PEM System ». Photonics 8, n^o 6 (24 mai 2021) : 184. http://dx.doi.org/10.3390/photonics8060184.

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As the application requirements of semiconductor lasers continue to increase, severe challenges are brought to the reliability of semiconductor lasers. In order to promote the study of laser failure, this paper proposes an effective failure analysis method for packaged semiconductor lasers with a simple sample preparation and home-made photon emission microscopy (PEM) system. The new simple sample preparation process for failure analysis is presented and the necessary polishing fixture is designed so that sample can be obtained without expensive and complex micro-/nano-processing. Two types of home-made PEM experimental systems were established for observing the failure from the front facet and active region of semiconductor lasers. Experimental results showed that, with the proposed sample preparation flow, the home-made PEM experimental system effectively observed the leakage defects from the front facet and dark spot defects (DSDs) in the active region of semiconductor lasers. The method can help researchers and laser manufactures to perform effective failure analysis of packaged semiconductor lasers.

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Idle, M., R. Cobb, J. Sullivan et J. Goodding. « Use of a Zero-Gravity Suspension System for Testing a Vibration Isolation System ». Journal of the IEST 41, n^o 6 (17 novembre 1998) : 42–46. http://dx.doi.org/10.17764/jiet.41.6.ux81795873715573.

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The Air Force Research Laboratory team has been confronted with many unique testing challenges in the Ballistic Missile Defense Organization sponsored Vibration Isolation and Suppression System (VISS) performance test program, VISS incorporates a combination passive/active vibration mitigation technology in a Stewart platform configuration to provide a mechanically quiet platform for a medium-wavelength, infrared camera. VISS actuator stiffnesses, insufficient to support the payload in a l-g field, require a gravity off-load system to simulate the free boundary conditions of space A performance test series characterized the test fixture dynamics, VISS payload dynamics and the open loop control system plant. Passive performance has been characterized and the active performance measured in the laboratory will be verified when VISS is on-orbit. VISS goals include demonstrating good passive-based vibration isolation at high frequencies, augmenting low-frequency isolation with closed loop control, suppressing an on-board disturbance due to a cryocooler, and demonstrating steering capabilities of the payload with a prescribed amplitude and spectral content.

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Plummer, Michael G. « Asian Integration and Its Implications for the EU “Post-Doha” ». Asian Economic Papers 13, n^o 1 (janvier 2014) : 53–79. http://dx.doi.org/10.1162/asep_a_00250.

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Asian economic cooperation and integration has become a key fixture of the global economic landscape in the 21st century. Over the past decade Asian economies established a large number of bilateral and a few sub-regional free trade areas that have facilitated the rise in intra-regional trade and regional production networks. More recently, the region has been active in embracing regionwide accords. The EU has been essentially left out of this process. This paper considers the economic costs of EU exclusion from the economic cooperation initiatives in Asia. It finds that, although on the whole the effects will be small, the EU could face significant trade diversion at the commodity level.

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Feng, Xing, Shijun Qin, Qingfeng Wang, Yongqi Gu, Jin Cao, XianFeng Chen, Xiaoye He et Xiao Li. « Development of active laser reflector for alignment and monitoring of large-scale scientific devices ». Journal of Instrumentation 17, n^o 09 (1 septembre 2022) : T09002. http://dx.doi.org/10.1088/1748-0221/17/09/t09002.

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Abstract As large-scale scientific devices like particle accelerators and tokamaks become bigger and more complex, efficient measurements are needed for these devices. At present, when laser trackers are used to measure these devices, manually rotating reflectors is needed in many circumstances, but it's inefficient and it's inappropriate to be used in the areas where human can't approach. To solve the problem, we designed an active laser reflector, which can rotate to a target angle position controlled by a host computer software. We designed a fixture to embed and clamp a spherically mounted retro-reflector (SMR). And two custom-designed motors are used to drive the SMR to rotate horizontally and vertically respectively. The shaft of the motor has a flange to match another flange on the load, which can reduce the coaxiality error between them. The motor control system consists of two motor controllers and a host computer software, and they communicate through WIFI. We made a prototype of the active laser reflector based on the design scheme and measured the offset of the SMR center, which is around ±0.23 mm. The active laser reflector we designed can increase the measuring and monitoring efficiency for large-scale scientific devices.

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